Merlin, a wizard on the cusp of adulthood, arrives in Camelot hoping to find a use for his burgeoning talent for magic. He is welcomed by Gaius, the court physician, but Merlin soon learns magic has been outlawed by King Uther, the tyrannical leader of the realm, its practice made punishable by death. When the Great Dragon summons Merlin to his cave, he tells the young wizard that he has a great destiny - to use his skills to keep the young Prince Arthur safe. But Merlin hates the flashy, arrogant Prince, and Arthur despises the wizard with equal fervour. So when an evil witch threatens Prince Arthur's life, Merlin finds himself tested - will he face up to his destiny to keep Arthur safe? And can he do so without getting caught?

Camelot is hosting its annual sword tournament and knights from throughout the realm have come to compete for its coveted title. Among those hoping to win the crown is Knight Valiant. Armed with a magical shield, Valiant will stop at nothing to win his prize. Merlin tries to expose Valiant as a cheat, but even those closest to him do not believe his claims. Battling with his faith, friendships and destiny, Merlin attempts to stop Valiant's evil scheme before Arthur becomes the next knight to die by his shield.

The fantasy-drama based on the King Arthur legend continues, as a deadly plague spreads through Camelot. When it seems that sorcery can be the only possible explanation, Merlin and Gaius race to find a cure, while Gwen is arrested and sentenced to death for practising witchcraft. Venturing deep beneath Camelot to unmask the true culprit, Merlin, Morgana and Arthur are faced with a terrifying beast, conjured by the evil sorceress Nimueh. Can they expose the truth before Gwen is executed?

The evil sorceress Nimueh (Michelle Ryan) is back to wreak havoc on Camelot. This time Merlin is her target, and she tricks the young warlock into drinking from a poisoned chalice, causing him to fall dangerously ill. Arthur must venture to the caves deep beneath the forest of Balor to obtain the antidote, but he does not realise he is walking into a trap. Determined to thwart his quest, Nimueh does everything she can to stop him. Can Arthur overcome these magical hurdles and make it back in time to save his friend?

On a trip to the forest, Merlin is attacked by a terrifying winged monster. Help comes from an unexpected quarter when a heroic stranger fights off the beast. His name? Lancelot. Keen to repay this debt, Merlin resolves to help his new friend become a Knight of Camelot. But at what cost? For Lancelot is not of noble blood, and to change the pages of destiny is a dangerous game. With the mysterious creature still on the loose, Merlin's actions could have disastrous consequences for Camelot - and for Arthur.

The fantasy adventure romp based on the legend of King Arthur continues. When the Lady Morgana is struck down with a mysterious illness, Gaius is at a loss for a cure. Thankfully a new physician, Edwin Muirden, is on hand to bring the King's ward back from the brink. As the stranger charms his way further into Camelot's court, winning over everyone from Uther to Merlin, Gaius begins to doubt his credentials. Just who is the mysterious newcomer and what does he want with the royal family? Gaius' loyalty and bravery are going to be tested to the limit if he is to find out.